This book looked utterly ordinary: a gray cover bearing the words Book of Yin Souls, made of plain paper with nothing remarkable about it. Yet it carried an immensely powerful yin aura, making it feel anything but ordinary—like some sinister, malevolent object.
Zhao Fu had high expectations for it. The first trial had given him a terrifying scroll capable of summoning a billion ghosts, so the second item certainly would not be poor. Once Zhao Fu examined the book's information, he was indeed overjoyed.
The book recorded a method for nurturing yin soul beasts, methods for fusing yin soul beasts, and methods for controlling them.
The yin soul beasts bred this way would mostly be first-tier, but as long as they were fused into the bodies of first-tier soldiers with matching attributes, those first-tier soldiers could be elevated to second-tier and gain the ability to manifest soul beasts.
As long as Zhao Fu used this method, he could possess vast numbers of second-tier soldiers, with strength comparable to that of an Outer Domain kingdom.
However, there were limitations. First, the yin soul beasts had to be raised by himself; only by raising more could he have more yin soul beasts fused into soldiers' bodies. Second, the soldiers being fused had to be soldiers transformed into yin soldiers after death.
Only such pure yin soldiers could fuse with yin soul beasts. Ordinary Netherworld yin soldiers could not, because they still counted as having their own lives rather than being transformed after death.
Great Qin currently had 1.2 billion yin soldiers. If it raised large numbers of yin soul beasts, Great Qin could immediately gain another 1.2 billion second-tier soldiers. To obtain more yin soldiers, it would need more Nine Nether King Seals, which required kingdom seals for conversion.
However, because the